Programmer for air jet texturing apparatus

ABSTRACT

The present programmer operates to produce variations in the bulkiness along the length of air jet textured yarns by producing an irregular pattern of impulses which does not repeat for a long length of time. The programmer includes a rotatable pattern wheel having depressions in the form of substantially radially extending grooves of irregular width and configuration on one face thereof. An air nozzle sensor is supported for movement in a generally radial direction of the pattern wheel to &#39;&#39;&#39;&#39;read&#39;&#39;&#39;&#39; the grooves as the pattern wheel rotates and to thereby produce periods of reduced air pressure in the system. An air pressure switch is operated by these reductions in the air pressure to cause the air jet texturing unit to form irregularly spaced slubs along the length of the yarn.

United States Patent 1191 Schrader et al.

[ 5] Sept. 17, 1974 PROGRAMMER FOR AIR JET TEXTURING APPARATUS [75]Inventors: Victor H. Schrader, Wilmington;

Richard J. Polney, New Castle; Peter W. Vermilyea, Newark, all of Del.

[73] Assignee: Enterprise Machine and Development Corporation, New

3,332,125 7/1967 Davis et a]. 28/].4

A19, SUPPLY Gray 28/].4 X Bartnicki 28/].4

[5 7 ABSTRACT The present programmer operates to produce variations inthe bulkiness along the length of air jet textured yarns by producing anirregular pattern of impulses which does not repeat for a long length oftime. The programmer includes a rotatable pattern wheel havingdepressions in the form of substantially radially extending grooves ofirregular width and configuration on one face thereof. An air nozzlesensor is supported for movement in a generally radial direction of thepattern wheel to read the grooves as the pattern wheel rotates and tothereby produce periods of reduced air pressure in the system. An airpressure switch is operated by these reductions in the air pressure tocause the air jet texturing unit to form irregularly spaced slubs alongthe length of the yarn.

14 Claims, 9 Drawing Figures PROGRAMMER FOR AIR JET TEXTURING APPARATUSThis invention relates generally to a programmer for an air jettexturing apparatus for producing variations in the bulkiness along thelength of fluid jet textured yarns and more particularly to a programmerfor producing irregularly spaced slubs along the length of the yarn.

Several different types of devices have been proposed for producingslubs along the length of an air jet textured yarn. Certain of thesedevices operate to vary the amount of air supplied to the air jet tothereby form slubs along the length of the yarn as it is being textured.Other program devices operate to vary the speed of the yarn being fed tothe air jet to thereby form slubs along the yarn. In either case, theprogram device produces impulses which change either the air supply orthe yarn feed. However, these known types of pattern devices have notbeen entirely satisfactory because they either do not provide asufficiently long repeat of the pattern or they are too complicated andexpensive, requiring highly skilled personnel to maintain pattern devicein proper operating order.

With the foregoing in mind, it is an object of the present invention toprovide a programming apparatus for producing irregularly spaced slubsalong the length of air jet textured yarn which is simple inconstruction, easily applied to the usual jet texturing apparatus, andrequires very little attention over long periods of operation.

The present programmer includes a rotatable pattern wheel having asubstantially smooth flat surface on one face thereof and a plurality ofspaced-apart depressions in the form of grooves extending in a generallyradial direction of the pattern wheel and being of irregular width andconfiguration. An air nozzle sensor is supported to direct air againstthe face of the pattern wheel as it is rotated at a predetermined speedso that a predetermined pressure is produced when the smooth surface ofthe face of the pattern wheel is passing the air nozzle and a reducedpressure is produced when one of the grooves passes the air nozzlesensor. An air pressure switch is operated by the variations produced inthe air pressure to either change the amount of air being supplied tothe air jet texturing unit or to change the speed of the yarn being fedto the air jet texturing unit so that slubs are formed at irregularintervals along the yarn. The air nozzle sensor is supported formovement across the face of the pattern wheel in timed relationship torotation of the pattern wheel and in a generally radial direction sothat different portions of the grooves are engaged by the air nozzlesensor during successive rotations of the pattern wheel to therebyincrease the length of repeat of the pattern of slubs.

Other objects and advantages of the invention will appear as thedescription proceeds, when taken in connection with the accompanyingdrawings, in which FIG. 1 is a somewhat schematic isometric view of onestation of a jet texturing apparatus and illustrating the programmer ofthe present invention associated therewith;

FIG. 2 is an enlarged front elevational view of the programmerillustrated in FIG. 1;

FIG. 3 is a top plan view of the programmer shown in FIG. 2;

FIG. 4 is an enlarged fragmentary sectional view through the air nozzlesensor, being taken substantially along the line 44 in FIG. 2;

FIG. 5 is an enlarged fragmentary view of one portion of the patternwheel shown in FIG. 2 and illustrating the manner in which the airnozzle sensor is moved inwardly and outwardly relative to the patternwheel;

FIG. 6 is a fragmentary sectional view taken substantially along theline 66 of FIG. 5;

FIG. 7 is a vertical sectional view through the air pressure switch ofthe programmer;

FIG. 8 is a modified form of programmer wherein the air nozzle sensor ismoved across the face of the pattern wheel by a different type ofcontrol; and

.FIG. 9 is another modified form of programmer illustrating a differenttype of control for moving the air nozzle sensor across the face of thepattern wheel.

The programmer of the present invention is illustrated in FIG. 1 asbeing associated with a particular type of air jet texturing apparatuswherein the rate of feed of the yarn is varied to thereby produce slubsalong the length of the yarn. However, it is to be understood that thepresent programmer may be associated with air jet texturing deviceswhich include means to vary the amount of air supplied to the air jet tothereby produce slubs along the length of the yarn.

The air jet texturing apparatus includes a yarn supply source in theform of a yarn supply package or bobbin 10 from which the yarn Y iswithdrawn. The yarn Y passes through a conventional type of tensiondevice, in the form of a tension disc 11, passes through a variable feeddevice, broadly indicated at 12, which will be presently described indetail, and is fed thereby into an air or fluid texturing jet 13. Fromthe jet 13, the yarn Y passes through a tension device, in the form of atension fork 14, passes over a roll where a suitable lubricant isapplied to the yarn, and is then wound-onto a suitable take-up package,indicated at 16. The yarn Y is guided onto the yarn take-up package 16by a yarn traversing guide 17 and the yarn take-up package 16 is rotatedby a suitable drive roll 18.

The variable feed device 12 includes a first feed rol 20 and a secondyarn feed roll 21, both of which are positioned between the yarn supplypackage 10 and the air jet 13. The yarn Y is directed above the upperperipheral surface of feed roller 20 by suitable yarn guide means, inthe form of a yarn guide eye 22 and a yarn guide roller 23 supported onthe outer end of a spring wire 24.

The first feed roll 20 is rotated at a relatively slow speed from anysuitable driven portion of the texturing machine. The second yarn feedroll 21 is rotated ata relatively fast speed by means of a drive belt28, which may engage different diameters of a stepped drive 'pulley 29fixed on the feed roll 21. The drive belt 28 is driven by a pulley 30fixed on a drive shaft 31. A rocker bracket 32 is pivotally supportedintermediate its ends and rotatably supports a first idler roll 33 atits upper end and a second idler roll 34 at its lower end. The

rocker bracket 32 is normally urged inwardly at its upper end, byresilient means not shown, so that the first idler roller 33 engages theyarn Y and moves the same into driving engagement with the first feedroll 20 and the yarn is fed to the jet 13 at the relatively slow rate toimpart a predetermined bulkiness to the yarn. The idler roller 34 isnormally maintained out of engagement with the lower feed roll 21 andthe yarn Y.

Operator means, not shown, is supported in a housing 35 and is operablyconnected to the rocker bracket 32 and, when the operator means isactuated in a manner to be presently described from the programmer ofthe present invention, the rocker bracket is moved inwardly at its lowerend so that the second idler roller 34 engages and moves the yarn Y intodriven engagement with the lower feed roll 21 to drive the yarn at thefaster rate. When the yarn is fed to the jet 13 at the faster rate, anincreased amount of bulk is imparted to the yarn to thereby produce aslub. The sudden increases in the rate at which theyarn is fed to thejet 13 causes greatly increased bulking of the yarn to form neps orslubs along the length of the yarn. The yarn is normally driven by thefast feed roll 21 for a very short period of time and the rocker bracket32 then moves the upper idler roll 32 in engagement with the slow feedroll 21 so that the yarn is then again fed to the jet 13 by the firstfeed roll 20 and at the relatively slow speed.

The variable feed device 12 is disclosed in detail in copendingapplication Ser. No. 289,106, filed Sept. 4, 1972, to which referencemay be made for details thereof. The type of feed device illustrated isonly one of several different types of feed devices which may beemployed with the programmer of the present invention. Also, as has beenmentioned, the programmer of the present invention may be utilized inconnection with a device for varying the amount of air supplied to theair jet 13 for producing slubs at irregular intervals along the lengthof the yarn.

The programmer of the present invention includes a rotatable patternwheel 40 with a flat substantially smooth surface on one face thereofand having a plurality of spaced apart openings, hollows, or depressionsprovided therein. The depressions are illustrated as being in the formof grooves 41 in the flat smooth face of the pattern wheel. As shown inFIG. 6, the grooves 41 are cut or etched inwardly on the smooth face ofthe pattern wheel to a small depth. However it is to be understood thatthe grooves 41 may be cut entirely through the pattern wheel 40 ifdesired. As shown in FIGS. 2 and the grooves 41 may be irregularlyspaced apart, may be of irregular width and configuration and extend ina direction generally radially of the pattern wheel 40. However, it isto be understood that the grooves 41 may be equally spaced, may be ofthe same width, and/or may extend inwardly of the pattern wheel 40 atany desired angle. Also, openings or depressions of other configurationsmay be provided on the smooth face of the pattern wheel 40. For example,a series of irregularly spaced holes of the same or different sizes maybe formed in the smooth face of the pattern wheel 40.

Drive means is provided for rotating the pattern wheel 40 at apredetermined speed and includes a stub shaft 42 (FIG. 2) on one end ofwhich the pattern wheel 40 is supported for rotation. The other end ofthe stub shaft 42 is fixed in a support plate 43 and a stepped pulley 44is rotatably supported on the stub shaft 42 and fixed to the patternwheel 40. A stepped drive pulley 45 is fixed on the output shaft of anelectric motor 46 which is fixed to the support plate 43. A drive belt47 drivingly connects the stepped pulleys 44, 45 and may be shiftedbetween the different steps of the pulleys to thereby vary therotational speed of the pattern wheel 40 relative to the electric motor46.

Air nozzle means in the form of an air nozzle sensor 50 in provided withan air outlet for directing air against one face of the pattern wheel 40(FIG. 4). The air nozzle sensor 50 is supported in one end of a controlarm 51 -for moving the air nozzle in a generally radial direction acrossthe face of the pattern wheel 40. Operator means is provided for movingthe control arm in the generally radial direction along one face of thepattern wheel and in timed relationship to rotation of the pattern wheel40, in a manner to be presently described.

Air supply means, schematically illustrated at 52 in FIG. 1, includes anair supply line 53 for directing air under a predetermined pressure tothe air nozzle sensor 50. A branch supply line 54 is communicativelyconnected at one end to the air supply line 53 and its other end issuitably connected to an air pressure operated switch, broadly indicatedat 55.

The medial portion of the control arm 51 is provided with a longitudinalslot which surrounds a pivot shaft 56 and pivotally supports the medialportion of the control arm 51. The inner end of the pivot shaft 56 isfixed in the support plate 43. The inner end of a drive pin 57 is fixedin and is eccentrically supported on the stepped drive pulley 45 and itsouter end is drivingly connected to the other end of the control arm 51.The stepped drive pulley 45 thus is used as a drive wheel for impartingmotion to the control arm 51 to move the air nozzle sensor 50 inwardlyand outwardly across the face of the pattern wheel 40 and in a generallyradial direction, as illustrated in dotted lines in FIG. 5.

The air pressure switch may be of any suitable conventional type and isshown in a somewhat schematic manner in FIG. 7 as including a flexiblediaphragm 60 which is operatively connected to an electric switch 61.Electric wires 62 are connected at one end to the switch 61 and at theother end to the operator means of the feed control device 12 which issupported in the housing 35. The air from the air supply 52 is directedthrough line 53 and out of the air outlet of the air nozzle sensor 50against the smooth face of the pattern wheel 40. A predetermined amountof air pressure is thus provided in the supply line 53, the branch line54, and in the air pressure switch 55.

When the air nozzle sensor 50 is passing over the smooth face of thepattern wheel 40, the air pressure is relatively high and maintains thediaphragm 60 in the raised position shown in FIG. 7 so that the electricswitch 61 is in the open position and the feed device 12 is feeding theyarn at a relatively slow rate by the first feed wheel 20 and the idlerroller 33. When a portion" of one of the grooves 41 passes the airnozzle sensor 50, the air pressure in the system is momentarily reducedas the air can escape through the groove 41. The diaphragm 60 in the airpressure switch 55 then moves downwardly to the level position so thatthe electric switch 61 is closed and the control means in the feeddevice 12 is actuated to move the idler roller 34 into engagement withthe second feed roller 21 and feed the yarn at a fast rate of speedso.that a slub is produced by the air jet 13. As soon as the groove 41has passed the air nozzle sensor 50, the air pressure in the system isagain increased and the air switch 55 is opened so that the yarn isagain fed at the slow rate by the first feed roll 20 and the idler roll33.

As the pattern wheel 40 and the stepped pulley 45 rotate, the controlarm 51 is moved forwardly and rearwardly on the pivot shaft 56 to movethe air nozzle sensor 50 in a generally radial direction across the faceof the pattern wheel, as illustrated in solid and dotted lines in FIG.5, to thereby vary the radial position at which the air nozzle sensor 50passes over the irregular grooves 41 in the pattern wheel 40. Thus, asone groove passes the air nozzle sensor 50, the sensor may be positionednear the outer periphery of the pattern wheel 40 and as the next groove41 passes the air nozzle, it may be positioned at a medial point or atan inner point on the pattern wheel 40. During the next successiverotation of the pattern wheel 40, the same groove may be engaged by theair nozzle sensor 50 at a different location to thereby produce adifferent type of slub. By varying the position of the drive belt 47 inthe grooves of the stepped pulleys 44, 45, the rotational speed of thepattern wheel 40 may be varied, relative to the rotational speed of thedrive wheel or stepped pulley 45 to thereby vary the position of the airnozzle sensor 50 during rotation of the pattern wheel 40.

Many of the parts of the modified form of programmer shown in FIG. 8 areidentical to the corresponding parts of the programmer shown in FIGS.1-7 and corresponding parts will bear like reference characters with theprime notation added. The operator means for.

moving the inner end of the control arm 51' and the air nozzle in agenerally radial direction along the face of the pattern wheel 40includes an eccentric cam wheel 65 which is rotated by the electricmotor 46 and engages the medial portion of the control arm 51. Thecontrol arm 51' supports the air nozzle sensor at its inner end and itsouter end is pivotally supported on the outer end of a pivot post 66connected at its inner end to the support plate 43'.

Resilient means, in the form of a tension spring 67, is connected at oneend to the medial portion of the control arm 51 and its other end isconnected to a suitable spring perch on the support plate 43. The spring67 normally urges the medial portion of the control arm 51 intoengagement with the eccentric cam wheel 65. The eccentric cam wheel 65imparts movement to the air nozzle sensor in a generally radialdirection as the pattern wheel 40' is rotated so that the radialposition of the air nozzle sensor is varied while the pattern wheel 40'is rotated.

The modified type of programmer illustrated in FIG. 9 is also verysimilar to the first two types of programmers and corresponding partswill bear like reference characters with the double prime notationadded. An eccentric cam wheel 70 is fixed on the output shaft of theelectric motor 46" and engages a roller 71 fixed on the outer end of thecontrol arm 51". The media] portion of the control arm 51" is supportedfor longitudinal sliding movement in slide plates 72 fixed on thesupport plate 43". Resilient means, in the form of a tension spring 73,maintains the roller 71 in contact with the eccentric cam wheel 70. Oneend of the spring 73 is supported on a rod 74 connected to the controlarm 51" and the other end is supported on a suitable spring perchconnected to the support plate 43". Thus, as the eccentric cam wheel 70rotates in timed relationship to rotation of the pattern wheel 40", thecontrol arm 51" moves inwardly and outwardly in a radial direction overthe face of the pattern wheel 40" so that the air nozzle sensorsupported thereby will pass the grooves 41" at varying radial positions.

The particular pattern of slubs which are to be produced by theprogrammer of the present invention may be easily varied by changing theposition of the drive belt 47 on the stepped pulleys 44, 45. Also, it isto be understood that pattern wheels having a difierent configuration ofgrooves, openings or depressions of other configurations may be providedfor use if entirely different patterns are utilized. In any event, theprogrammer of the present invention is adapted to produce slubs in theair jet textured yarn at irregular intervals over a long pattern repeat.Also, the programmer of the present invention is relatively simple inoperation and construction and may be maintained by an operator withvery little training.

In the drawings and specification, there has been'set forth a preferredembodiment of the invention, and although specific terms are employed,they are used in a.

generic and descriptive sense only and not for purposes of limitation.

That which is claimed is:

1. A pattern device for controlling the formation of slubs produced byan air jet unit during a yarn texturing operation comprising a. arotatable pattern wheel having a flat substantially smooth surface onone face thereof, and including a plurality of spaced-apart depressionsin said one face,

b. drive means for rotating said pattern wheel at a predetermined speed,

0. air nozzle means having an air outlet for directing air against saidone face of said pattern wheel,

(1. air supply means for directing air to said air nozzle means toprovide a predetermined pressure when said smooth surface of said oneface is passing said air nozzle means and to provide a reduced pressurewhen one of said depressions passes said air nozzle means, and

e. an air pressure switch operated by variations in air pressure in saidair supply means and being operable to cause the formation of slubs bysaid air jet in accordance with the variations in air pressureproducedby said depressions in said pattern wheel.

2. A pattern device according to claim 1 wherein said depressionscomprise extending in a direction generally radially of said patternwheel.

3. A pattern device according to claim 2 wherein the grooves in said oneface of said pattern wheel are of irregular width and configuration.

4. A pattern device according to claim 1 including a control am havingone end supporting said air nozzle means for generally radial movementacross said one face of said pattern wheel, and operator means formoving said one end of said control arm and said nozzle in a generallyradial direction along said one face of said pattern wheel in timedrelationship to rotation of said pattern wheel.

5. A pattern device according to claim 4 wherein said operator meanscomprises a drive wheel, for imparting movement to said control arm, anddrive means for rotating said drive wheel in timed relationship withrotation of said pattern wheel.

6. A pattern device according to claim 5 wherein said drive means forsaid drive wheel is an electric motor.

7. A pattern device according to claim wherein said drive means (b) forrotating said pattern wheel comprises a first stepped pulley fixed tosaid pattern wheel, a second stepped pulley fixed to said drive wheel,and an endless belt drivingly connecting said first and second pulleyswhereby the position of said belt may be varied on said stepped pulleysto vary the speed of rotation of said pattern wheel relative to thespeed of said drive wheel.

8. A pattern device according to claim 7 including a drive pineccentrically supported at one end on said drive wheel and beingconnected to the other end of said control arm, and a pivot shaftsupporting a medial portion of said control arm for longitudinalmovement on said pivot shaft as movement is imparted to said control armby said drive pin.

9. A pattern device according to claim 5 including means pivotallysupporting the other end of said control arm, and wherein said drivewheel comprises an eccentric cam wheel engaging a medial portion of saidcontrol arm for imparting movement to said control arm, and resilientmeans maintaining the medial portion of said control arm in engagementwith said eccen tric cam wheel.

10. A pattern device according to claim 5 including means supporting themedial portion of said control arm for longitudinal sliding movement,and wherein said drive wheel comprises an eccentric cam wheel engagingthe other end of said control arm for imparting longitudinal movementthereto, and resilient means maintaining the said other end portion ofsaid control arm in engagement with said eccentric cam wheel.

11. In a yarn texturing device including a yam supply, a yarn take-upspaced from said yarn supply, an air jet between said supply andtake-up, means for feeding the yarn from said supply to said take-up andthrough said air jet, and slub forming means operable to form slubs inthe yarn and at spaced intervals therealong, the combination therewithof pattern means for controlling the formation of the slubs in anirregular manner, said pattern means comprising a. a rotatably patternwheel having a flat substantially smooth surface on one face thereof,and including a plurality of spaced-apart depressions in said one face,

b. drive means for rotating said pattern wheel at a predetermined speed,

c. air nozzle means having an air outlet for directing air against saidone face of said pattern wheel,

d. air supply means for directing air to said air nozzle means toprovide a predetermined pressure when said smooth surface of said oneface is passing said air nozzle means and to provide a reduced pressurewhen one of said depressions passes said air nozzle means, and

f. an air pressure switch operated by variations in air pressure in saidair supply means for actuating said slub forming means.

12. A yarn texturing device according to claim 11 wherein saiddepressions comprise grooves extending in a direction generally radiallyof said pattern wheel.

13. A yarn texturing device according to claim 11 wherein said slubforming means comprises yarn feed control means for increasing the rateof feed of the yarn to said air jet to form slubs when said yarn feedcontrol means is actuated and wherein said air pressure switch isoperatively connected to said yarn feed control means to actuate thesame each time one of said depressions passes said air nozzle means.

14. A yarn texturing device according to claim 12 wherein the grooves insaid one face of said pattern wheel are of irregular width andconfiguration.

1. A pattern device for controlling the formation of slubs produced by an air jet unit during a yarn texturing operation comprising a. a rotatable pattern wheel having a flat substantially smooth surface on one face thereof, and including a plurality of spaced-apart depressions in said one face, b. drive means for rotating said pattern wheel at a predetermined speed, c. air nozzle means having an air outlet for directing air against said one face of said pattern wheel, d. air supply means for directing air to said air nozzle means to provide a predetermined pressure when said smooth surface of said one face is passing said air nozzle means and to provide a reduced pressure when one of said depressions passes said air nozzle means, and e. an air pressure switch operated by variations in air pressure in said air supply means and being operable to cause the formation of slubs by said air jet in accordance with the variations in air pressure produced by said depressions in said pattern wheel.
 2. A pattern device according to claim 1 wherein said depressions comprise extending in a direction generally radially of said pattern wheel.
 3. A pattern device according to claim 2 wherein the grooves in said one face of said pattern wheel are of irregular width and configuration.
 4. A pattern device according to claim 1 including a control arm having one end supporting said air nozzle means for generally radial movement across said one face of said pattern wheel, and operator means for moving said one end of said control arm and said nozzle in a generally radial direction along said one face of said pattern wheel in timed relationship to rotation of said pattern wheel.
 5. A pattern device according to claim 4 wherein said operator means comprises a drive wheel, for imparting movement to said control arm, and drive means for rotating said drive wheel in timed relationship with rotation of said pattern wheel.
 6. A pattern device according to claim 5 wherein said drive means for said drive wheel is an electric motor.
 7. A pattern device according to claim 5 wherein said drive means (b) for rotating said pattern wheel comprises a first stepped pulley fixed to said pattern wheel, a second stepped pulley fixed to said drive wheel, and an endless belt drivingly connecting said first and second pulleys whereby the position of said belt may be varied on said stepped pulleys to vary the speed of rotation of said pattern wheel relative to the speed of said drive wheel.
 8. A pattern device according to claim 7 including a drive pin eccentrically supported at one end on said drive wheel and being connected to the other end of said control arm, and a pivot shaft supporting a medial portion of said control arm for longitudinal movement on said pivot shaft as movement is imparted to said control arm by said drive pin.
 9. A pattern device according to claim 5 including means pivotally supporting the other end of said control arm, and wherein said drive wheel comprises an eccentric cam wheel engaging a medial portion of said control arm for imparting movement to said control arm, and resilient means maintaining the medial portion of said control arm in engagement with said eccentric cam wheel.
 10. A pattern device according to claim 5 including means supporting the medial portion of said control arm for longitudinal sliding movement, and wherein said drive wheel comprises an eccentric cam wheel engaging the other end of said control arm for imparting longitudinal movement thereto, and resilient means maintaining the said other end portion of said control arm in engagement with said eccentric cam wheel.
 11. In a yarn texturing device including a yarn supply, a yarn take-up spaced from said yarn supply, an air jet between said supply and take-up, means for feeding the yarn from said supply to said take-up and through said air jet, and slub forming means operable to form slubs in the yarn and at spaced intervals therealong, the Combination therewith of pattern means for controlling the formation of the slubs in an irregular manner, said pattern means comprising a. a rotatably pattern wheel having a flat substantially smooth surface on one face thereof, and including a plurality of spaced-apart depressions in said one face, b. drive means for rotating said pattern wheel at a predetermined speed, c. air nozzle means having an air outlet for directing air against said one face of said pattern wheel, d. air supply means for directing air to said air nozzle means to provide a predetermined pressure when said smooth surface of said one face is passing said air nozzle means and to provide a reduced pressure when one of said depressions passes said air nozzle means, and f. an air pressure switch operated by variations in air pressure in said air supply means for actuating said slub forming means.
 12. A yarn texturing device according to claim 11 wherein said depressions comprise grooves extending in a direction generally radially of said pattern wheel.
 13. A yarn texturing device according to claim 11 wherein said slub forming means comprises yarn feed control means for increasing the rate of feed of the yarn to said air jet to form slubs when said yarn feed control means is actuated and wherein said air pressure switch is operatively connected to said yarn feed control means to actuate the same each time one of said depressions passes said air nozzle means.
 14. A yarn texturing device according to claim 12 wherein the grooves in said one face of said pattern wheel are of irregular width and configuration. 